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A006730 Series for second perpendicular moment of square lattice (eventually changes sign).
(Formerly M1841)
4
0, 2, 8, 24, 64, 156, 358, 786, 1664, 3434, 6902, 13656, 26464, 50772, 95754, 179442, 331294, 609496, 1106106, 2004852, 3586874, 6423028, 11351274, 20126538, 35191190, 61883196, 107179834, 187216848, 321395596, 558468104 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The first negative term is the 66th.

REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

I. Jensen, Table of n, a(n) for n = 0..171 (from Jensen link below)

J. W. Essam et al., Analysis of extended series for bond percolation on the directed square lattice, Phys. Rev. B 33 (1986), 1982-1986.

J. W. Essam, A. J. Guttmann and K. De'Bell, On two-dimensional directed percolation, J. Phys. A 21 (1988), 3815-3832.

I. Jensen, More terms

Iwan Jensen, Anthony J. Guttmann, Series expansions of the percolation probability for directed square and honeycomb lattices, J. Phys. A 28 (1995), no. 17, 4813-4833.

CROSSREFS

Cf. A006461, A006727, A006728, A006729.

Sequence in context: A222808 A075216 A127790 * A131135 A292218 A097064

Adjacent sequences:  A006727 A006728 A006729 * A006731 A006732 A006733

KEYWORD

sign

AUTHOR

N. J. A. Sloane, Simon Plouffe

STATUS

approved

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Last modified December 13 14:58 EST 2017. Contains 295958 sequences.